This story has been updated.
A tip that grounded a US Airways flight on Thursday morning was a hoax, according to NBC News.
The flight, bound for Dallas, returned to Philadelphia after officials received a call that a man had brought liquid explosives on board. The man, who was escorted off the plane in handcuffs, was the victim of an apparent birthday prank.
Local TV stations broadcast footage of police with dogs on the tarmac. Airport spokeswoman Victoria Lupica told The Washington Post that 98 passengers were on board and that no other flights were affected.